Conventionally, research has been directed toward a technology forming a pn junction via a diffusion layer on the surface of a small-diameter spherical semiconductor element composed of a p or n type semiconductor, connecting many of these spherical semiconductor elements in parallel to a common electrode, and putting to practical use for a solar cell or semiconductor photocatalyst.
U.S. Pat. No. 3,998,659 discloses a solar cell configured such that a p type diffusion layer is formed on the surface of an n type spherical semiconductor, the diffusion layers of many spherical semiconductors are connected to a common membrane electrode (positive electrode), and the n type cores of many spherical semiconductors are connected to a common membrane electrode (negative electrode).
U.S. Pat. No. 4,021,323 discloses a solar energy converter (semiconductor module) in which p type spherical semiconductor elements and n type spherical semiconductor elements are disposed in series, these semiconductors are connected to a common film-like electrode, and the diffusion layers of these semiconductor elements are brought into contact with a common electrode in the electrolyte, so that the electrolyte will undergo electrolysis when irradiated with sunlight.
With the modules featuring spherical cells disclosed in U.S. Pat. Nos. 4,582,588 and 5,469,020, each spherical cell is attached by being connected to a common sheet-like electrode, so this configuration is suitable for the parallel connection of a plurality of cells, but not for the serial connection.
Meanwhile, as discussed in U.S. Pat. Nos. 6,204,545 and 6,294,822, the inventor of the present invention has proposed a granular light-receiving or light-emitting semiconductor device in which a diffusion layer, a pn junction, and a pair of electrodes are formed on spherical semiconductor elements composed of p type or n type semiconductor, and in U.S. Pat. No. 6,204,545 the inventor has proposed a semiconductor module that is applicable to solar cells, photocatalyst apparatuses used in the electrolysis of water, a variety of light emitting devices, and color displays, and so forth. With this semiconductor module, if any of the semiconductor device in any of the serial connection becomes open through malfunction, current stops flowing to the serial circuit including that semiconductor element, the remaining properly-functioning semiconductor devices in the serial connection also cease functioning, and the output of the semiconductor module decreases.
In view of this, the inventors have come up with a serial/parallel connection structure in which a plurality of semiconductor cells are disposed in a matrix, the semiconductor cells in each column are connected in series, and the semiconductor cells in each row are connected in parallel, and have filed several international patent applications.
However, the semiconductor module in U.S. Pat. No. 6,204,545 employs a structure in which the electrodes of the semiconductor cells are connected so that a plurality of semiconductor cells are connected in series, and these serial connections are arrayed in a plurality of planar rows, and the pair of electrodes of each semiconductor cell is extremely small, so when the above-mentioned serial/parallel connection structure is employed, manufacture becomes complicated, it is difficult to produce a large semiconductor module, and the cost of manufacturing a semiconductor module rises.
As discussed above, the spherical semiconductor device proposed by the inventor has a small diameter of only about 1 to 3 mm, so when it is applied in a solar panel or light emitting panel, for instance, a large number of these spherical semiconductor devices end up being disposed just a few millimeters apart in a matrix. Because so many of the spherical semiconductor devices are required in this case, manufacturing expense become higher. With a solar panel, it is possible to reduce the number of spherical semiconductor devices needed by additionally providing the spherical semiconductor devices in each column with a cylindrical condensing lens, so that the spacing between columns is increased. However, the position and orientation of the condensing lens must be varied according to the incident direction of the sunlight, and also a complex and expensive mechanism is needed to movably support and control the orientation of the condensing lens, so this situation is impractical.
Meanwhile, in the case of a light emitting panel used for lighting or display, the light emitted from the small-diameter spherical semiconductor device tends to be excessively bright, and it is difficult to construct a light emitting panel that emits soft light of the proper brightness.
The object of the present invention is to provide a light-receiving semiconductor apparatus with improved condensing function that condenses light in a light-receiving spherical semiconductor device; a light-receiving semiconductor apparatus with improved condensing function and which is less apt to be affected by the malfunction of some of the spherical semiconductor devices when a plurality of spherical semiconductor device are disposed in a plurality of rows and a plurality of columns; a light-receiving semiconductor apparatus with improved condensing function and in which a plurality of spherical semiconductor devices disposed in one or more columns are connected in parallel in each column unit; and a light-emitting semiconductor apparatus with improved light diffusion function that diffuses the light emitted from a light-emitting spherical semiconductor device.